Identification panels are known in the form of safety and health protection markers in workplaces. They may be configured in particular as prohibition signs, as imperative signs, as warning signs, as rescue signs, as fire protection signs or merely as information signs.
Machines of a very wide variety of kinds, as well, are provided with identification panels in order to inform the user of possible hazards or particular aspects of the machines' operation.
Identification panels of this kind are customarily configured as film stickers, or plate-like supports bearing coatings or printing are used, and are attached to the machine in a variety of ways.
In the case of machines which are used in the food-processing industry, however, specific problems arise, which make it problematic to use customary identification panels available on the market.
A first issue is the required compatibility of the materials used with foods, including compatibility with drinking-water. This means that the materials used ought to have undergone approval as food contact material.
A further factor is that in contrast to appliances used in the household, for example, machines which are used in the food-processing industry must be cleaned regularly in accordance with stringent protocols. The cleaning agents used in such operations are often extremely aggressive, and are used in different stages of dilution in accordance with the particular country and the protocol in force there. Furthermore, in the course of cleaning, the machine surfaces and hence also any identification panels mounted thereon are also subject to severe mechanical stress, by means of brushes or high-pressure cleaners, for instance. Under these conditions as well, therefore, materials used for identification panels must be suitable for use on a food-processing machine and may not, for example, suffer corrosion, exhibit any propensity toward fragmentation or breakage, and may not come apart.
Trials with identification panels available on the market have shown that they do not durably withstand intact the chemical and mechanical exposure associated with regular cleaning operations. Products tested were not only film stickers (adhered to a stainless-steel support sheet) but also stainless-steel identification panels with a coated-on pictogram and an overlying coating of protective varnish (the varnish used in each case was one declared as acid-resistant), and also Resopal plates. They were placed in cleaning agent for a period of several hours, and were sprayed off at regular intervals with a high-pressure cleaner. In all cases, after each of the test procedures, the identification panels showed relatively severe damage. Either the pictograms had detached (stickers), or the marking—after having been attacked by the chemical cleaner—did not stand up to exposure to the high-pressure cleaner (varnished stainless-steel support sheet), or the support material was swollen and the pictogram and constituents of the support material became detached (Resopal panel). A Resopal panel with a propensity to fragment, a varnished metal sheet, or remnants of sticker which have detached, furthermore, are also problematic in particular because fragments, detached varnish or remnants of sticker will not be recognized by metal detectors, which are used in order to pickup any extraneous metallic substances, and will at worse enter the food processing operation.
If the aim is to ensure that a machine is properly labeled over the long term, therefore, the identification panels must be renewed regularly. This requires not only the replacement of damaged markers but also the regular monitoring of the machine's labeling, and an associated administrative cost.
Another consideration is that information panels used ought also to have been designed in such a way that they can be attached to the food-processing machines in accordance with hygiene considerations. Thus, for example, stickers, at whose regularly slightly detaching edges residues of cleaning agent or food may collect, are not suitable for use on machines which are employed for industrial food processing. The same is also true of other kinds of markers which cannot be easily mounted by the user and demounted for purposes of cleaning, or which, even in the machine-mounted state, allow easy cleaning of any gaps which form between machine surface and identification panel.